noisy pipework?????

[Ginger plumbing]

Hi been round to a friends house who has a banging noise. This happens when you run the hot tap then turn it off and then you get this strange slight bang from the pipework. Boiler has been serviced recently but cant imagine it has any thing to do with this as didnt touch water side of anything but friend said that this has only recently started happening. can any one help??? many thanks.

 

[topted22002]

install a water hammer arrester as close to the source of the problem as possible. This includes a body of air which is isolated and sealed from contact with water so that it remains effective ongoing.

 

[AWheating]

what type of hot water system is installed?

 

[wiggers]

If you have a cistern in loft isolate the water going to it and change the ball valve and ball there about a tenner job sorted!!

 

[clarky101]

or it could be the tap, it happens when the inside's are shot....

 

[Ginger plumbing]

It's on a sealed system friend has a combi, have been told that fitting a non return valve on main supply inside house will fix it but am unsure what do u think?. Also can't be taps as friend also says happens now when washing machine is working.

 

[jhon lennon]

your friend is experiencing a thing called water hammer the non return valve wont make any difference to a combi so its a shock arrester that's needed the washer is hot and cold fill isn't it i am sure it must be to be affected the boiler service made a bell ring because if the flow rate was ajusted because maybe the tap wasn't running hot enough the restriction could be causing the noise and that would explain the banging from the pipes after the tap has been closed due to the very hot warter causing expansion hope this is some use to you

 

[Ginger plumbing]

Boiler is only a cold fill as has built in heating element and boiler Is only a few years old so as got a very low reading with Flue gas analyser I didn't need to touch much else on the boiler just a general clean inside so service can't be to blame

 

[AWheating]

Fitting a non return valve would likely cause more water hammer and many combi manufactures suggest fitting a shock arrestor if a non return vavle is fitted on the cold main. Have they had a water meter fittted recently?

If the noise only happens at one tap it could be the tap needs looking at, if it happens on all hot taps then its probably water hammer. Turning the main stop tap down may help this as it will decrease the flow (not pressure) causing less pressure shock (has the water pressure/flow increased recently or has the water been turned off and then back on?). You could also consider checking the pipework clipping is adequate. If all else fails a mini arrestor could be the answer.

mixer taps and quarter turn levers will always show up water hammer more than other tap types because of the speed they shut off.

 

[Ginger plumbing]

Thanks for your replies. Friend has mentioned this bangin happens when hot & cold taps are turned off quickly only and also when washing machine is in use. Water has not recently been isolated so I'll check pipe clips next time I'm there and try turning stopcock if that fails then mini rester it is.

 

[Billy Bob Bob]

probably lack of clips,partly worn taps and to high a water pressure

 

[impman]

I get exactly the same thing! Varying degrees of banging when any water is turned off, I can actually see the cold water pipes vibrate in my kitchen!